SOLUTION: i just need help on setting up this problem, after the first step i will probably know what to do ... x2=+9x+20 (the X is supposed to be squared) im supposed to just factor the

Algebra ->  Polynomials-and-rational-expressions -> SOLUTION: i just need help on setting up this problem, after the first step i will probably know what to do ... x2=+9x+20 (the X is supposed to be squared) im supposed to just factor the       Log On


   

Question 724739: i just need help on setting up this problem, after the first step i will probably know what to do ... x2=+9x+20
(the X is supposed to be squared)
im supposed to just factor the trinomial
Answer by josmiceli(19441) About Me  (Show Source):
You can put this solution on YOUR website!
+x%5E2+=+9x+%2B+20+
Subtract +9x+ from both sides
+x%5E2+-+9x+=+20+
Complete the square. Take 1/2 of the +-9+,
square it, and add it to both sides
+x%5E2+-+9x+%2B+%28+-9%2F2+%29%5E2+=+20+%2B+%28+-9%2F2+%29%5E2+
+x%5E2+-+9x+%2B+20.25+=+20+%2B+20.25+
+%28+x+-+4.5+%29%5E2+=+40.25+
Take the square root of both sides
+x+-+4.5+=+sqrt%28+40.25+%29+
and
+x+-+4.5+=+-sqrt%28+40.25+%29+
The factors are
++x+-+4.5+%2B+sqrt%28+40.25+%29+ and
++x+-+4.5+-+sqrt%28+40.25+%29+